A test device for a display panel and a method of testing the same are provided. The test device for a display panel includes a luminance measurement unit that measures a luminance value of a display panel including a plurality of pixels, and a controller that determines a voltage value of a data signal corresponding to a target luminance value, receives a measured luminance value of a pixel to which the data signal is supplied from the luminance measurement unit from among the plurality of pixels, compares the measured luminance value and the target luminance value, and outputs a control signal that changes a first power source voltage value supplied from a power source voltage supply unit to the pixel until the measured luminance value does not coincide with the target luminance value.
Legal claims defining the scope of protection, as filed with the USPTO.
1. A test device for a display panel, comprising: a luminance measurement unit configured to measure a luminance value of the display panel comprising a plurality of pixels; and a controller configured to determine a voltage value of a data signal corresponding to a target luminance value, to receive a measured luminance value of a pixel to which the data signal is supplied from the luminance measurement unit from among the plurality of pixels, configured to compare the measured luminance value and the target luminance value, to correct the voltage value of the data signal until the measured luminance value coincides with the target luminance value, configured to output a control signal, after the measured luminance value coincides with the target luminance value, that changes a first power source voltage value supplied from a power source voltage supply unit to the pixel until the measured luminance value does not coincide with the target luminance value, and configured to set, as an output first power source voltage value, the first power source voltage value used immediately before the controller determines the measured luminance value does not coincide with the target luminance value.
2. The test device of claim 1 , wherein the power source voltage supply unit is configured to receive the control signal, to generate the first power source voltage according to the control signal, and to output the first power source voltage to the pixel.
3. The test device of claim 2 , wherein the power source voltage supply unit is configured to generate a second power source voltage and to supply the second power source voltage to the pixel, wherein a current corresponding to a voltage of the data signal and the second power source voltage flows to the pixel.
4. The test device of claim 1 , wherein the measured luminance value is compared with the target luminance value, and the first power source voltage value is increased to a maximum voltage value within a voltage range where the measured luminance value coincides with the target luminance value.
5. The test device of claim 1 , wherein the first power source voltage value is changed from a maximum voltage value of a voltage range corresponding to a saturation region of a driving current of the pixel to a voltage value having a voltage difference of a driving voltage margin of the pixel from the maximum voltage value.
6. The test device of claim 1 , wherein the control signal sequentially raises the first power source voltage value within a voltage range corresponding to a saturation region of a driving current of the pixel.
7. The test device of claim 1 , wherein the measured luminance value of the pixel that emits light corresponding to a driving current corresponding to an initial data signal is compared with the target luminance value, and when the measured luminance value does not coincide with the target luminance value, the voltage value of the data signal corresponding to the target luminance value is determined by correcting a voltage value of the initial data signal.
8. The test device of claim 1 , further comprising a data driver configured to supply the determined voltage value of the data signal to each of the plurality of pixels of the display panel.
9. The test device of claim 8 , wherein the data driver comprises a data storage unit configured to store information including the target luminance value according to an initial data signal, reference voltage data corrected according to the data signal, and a voltage value of a corresponding data signal determined by correction.
10. A method of testing a display panel, the method comprising: measuring a luminance value of a pixel receiving a data signal; comparing the measured luminance value to a target luminance value; correcting a voltage value of the data signal and again measuring the luminance value until the measured luminance value coincides with the target luminance value; changing a first power source voltage value applied to the pixel within a voltage range and again measuring the luminance value until the measured luminance value does not coincide with the target luminance value; determining an immediately previous first power source voltage value when the measured luminance value does not coincide with the target luminance value; and setting the immediately previous first power source voltage value as an output first power source voltage value.
11. The method of claim 10 , wherein the changing the first power source voltage value comprises adjusting the first power source voltage value of the pixel while sequentially raising the first power source voltage value within the voltage range.
12. The method of claim 10 , wherein the voltage range corresponds to a saturation region of a driving current of the pixel.
13. The method of claim 10 , wherein the output first power source voltage value is a maximum voltage value of the voltage range where the measured luminance value coincides with the target luminance value.
14. The method of claim 10 , wherein the output first power source voltage value is a maximum voltage value of the voltage range corresponding to a saturation region of a driving current of the pixel.
15. The method of claim 10 further comprising determining a final output first power source voltage value to be a voltage value that is the output first power source voltage value reduced by a driving voltage margin of the pixel after the determining of the immediately previous first power source voltage value, and setting the immediately previous first power source voltage value as the output first power source voltage value.
16. The method of claim 10 further comprising determining the voltage value of the data signal corresponding to the target luminance value before changing the first power source voltage value.
17. The method of claim 16 , further comprising determining the voltage value of the data signal corresponding to the target luminance value by: emitting light from the pixel by supplying an initial data signal and determining the measured luminance value of the pixel; and comparing the measured luminance value and the target luminance value and correcting the voltage value of the data signal and determining a voltage value of the initial data signal when the measured luminance value does not coincide with the target luminance value.
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August 30, 2010
November 25, 2014
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